Add input retriggering with configurable rate and offset

4 files changed, 157 insertions, 45 deletions

diff --git a/src/gba/gba.h b/src/gba/gba.h
index 8ba3de5..b5868f0 100644
--- a/src/gba/gba.h
+++ b/src/gba/gba.h
@@ -327,6 +327,117 @@ key_hold(u32 key) {
     return key_curr & key_prev & key;
 }
 
+// Stores number of frames since a keay was pressed.
+typedef struct Controller {
+    int key_up;
+    int key_down;
+    int key_left;
+    int key_right;
+    int key_select;
+    int key_start;
+    int key_b;
+    int key_a;
+    int key_l;
+    int key_r;
+} Controller;
+
+static Controller ctrl = {0};
+
+#define RETRIG_OFFSET 16
+#define RETRIG_FRAMES 3
+
+static inline
+bool
+_key_retrig(int key, int offset, int frames) {
+    if (key_tap(key)) {
+        return true;
+    }
+    switch (key) {
+        case KEY_L: {
+            if (key_hold(key)) {
+                if (ctrl.key_l < offset) { return false; }
+                if (ctrl.key_l % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_R: {
+            if (key_hold(key)) {
+                if (ctrl.key_r < offset) { return false; }
+                if (ctrl.key_r % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_A: {
+            if (key_hold(key)) {
+                if (ctrl.key_a < offset) { return false; }
+                if (ctrl.key_a % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_B: {
+            if (key_hold(key)) {
+                if (ctrl.key_b < offset) { return false; }
+                if (ctrl.key_b % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_SELECT: {
+            if (key_hold(key)) {
+                if (ctrl.key_select < offset) { return false; }
+                if (ctrl.key_select % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_START: {
+            if (key_hold(key)) {
+                if (ctrl.key_start < offset) { return false; }
+                if (ctrl.key_start % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_UP: {
+            if (key_hold(key)) {
+                if (ctrl.key_up < offset) { return false; }
+                if (ctrl.key_up % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_DOWN: {
+            if (key_hold(key)) {
+                if (ctrl.key_down < offset) { return false; }
+                if (ctrl.key_down % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_LEFT: {
+            if (key_hold(key)) {
+                if (ctrl.key_left < offset) { return false; }
+                if (ctrl.key_left % frames == 0) { return true; }
+            }
+        } break;
+        case KEY_RIGHT: {
+            if (key_hold(key)) {
+                if (ctrl.key_right < offset) { return false; }
+                if (ctrl.key_right % frames == 0) { return true; }
+            }
+        } break;
+    }
+    return false;
+}
+
+static inline
+bool
+key_retrig(int key) {
+    return _key_retrig(key, RETRIG_OFFSET, RETRIG_FRAMES);
+}
+
+static inline
+void
+update_controller(void) {
+    if (key_pressed(KEY_UP)) { ctrl.key_up++; } else if (key_released(KEY_UP)) { ctrl.key_up = 0; }
+    if (key_pressed(KEY_DOWN)) { ctrl.key_down++; } else if (key_released(KEY_DOWN)) { ctrl.key_down = 0; }
+    if (key_pressed(KEY_LEFT)) { ctrl.key_left++; } else if (key_released(KEY_LEFT)) { ctrl.key_left = 0; }
+    if (key_pressed(KEY_RIGHT)) { ctrl.key_right++; } else if (key_released(KEY_RIGHT)) { ctrl.key_right = 0; }
+    if (key_pressed(KEY_L)) { ctrl.key_l++; } else if (key_released(KEY_L)) { ctrl.key_l = 0; }
+    if (key_pressed(KEY_R)) { ctrl.key_r++; } else if (key_released(KEY_R)) { ctrl.key_r = 0; }
+    if (key_pressed(KEY_A)) { ctrl.key_a++; } else if (key_released(KEY_A)) { ctrl.key_a = 0; }
+    if (key_pressed(KEY_B)) { ctrl.key_b++; } else if (key_released(KEY_B)) { ctrl.key_b = 0; }
+    if (key_pressed(KEY_SELECT)) { ctrl.key_select++; } else if (key_released(KEY_SELECT)) { ctrl.key_select = 0; }
+    if (key_pressed(KEY_START)) { ctrl.key_start++; } else if (key_released(KEY_START)) { ctrl.key_start = 0; }
+}
+
 //
 // Direct Memory Access (DMA)
 //
diff --git a/src/main.c b/src/main.c
index 1562565..6b7619f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -24,7 +24,7 @@ WITH REGARD TO THIS SOFTWARE.
 //  + Fix scale being active for noise channel (makes no sense)
 //  + Save scale on metadata
 //  + Allow using B + dpad to nudge trigs. This will potentially mean switching
-//  - Hold L/R retriggers at short intervals?
+//  + Hold L/R retriggers at short intervals?
 //    to key release to enable trigs.
 //  - Fix any bugs we currently have
 //  - Add an envelope to ch3, would need to work with a timer in order to make
@@ -192,6 +192,7 @@ handle_input(void) {
 
 void
 update(void) {
+    update_controller();
     if (next_scene != scene) {
         scene = next_scene;
         clear_screen = true;
diff --git a/src/sequencer.c b/src/sequencer.c
index a032481..3433da1 100644
--- a/src/sequencer.c
+++ b/src/sequencer.c
@@ -442,7 +442,7 @@ handle_channel_selection(void) {
             }
         }
         redraw_params = true;
-    } else if (key_tap(KEY_L)) {
+    } else if (key_retrig(KEY_L)) {
         s32 inc = -1;
         if (key_hold(KEY_SELECT)) {
             inc = -12;
@@ -466,7 +466,7 @@ handle_channel_selection(void) {
             }
         }
         redraw_trigs = true;
-    } else if (key_tap(KEY_R)) {
+    } else if (key_retrig(KEY_R)) {
         s32 inc = 1;
         if (key_hold(KEY_SELECT)) {
             inc = 12;
@@ -491,16 +491,16 @@ handle_channel_selection(void) {
         }
         redraw_trigs = true;
     }
-    if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_RIGHT)) {
         trig_selection_loc = 0;
         param_selection_loc = 0;
         input_handler = handle_trigger_selection;
         redraw_params = true;
-    } else if (key_tap(KEY_LEFT)) {
+    } else if (key_retrig(KEY_LEFT)) {
         input_handler = handle_pattern_selection;
         param_selection_loc = 0;
         redraw_params = true;
-    } else if (key_tap(KEY_UP)) {
+    } else if (key_retrig(KEY_UP)) {
         if (channel_selection_loc == 0) {
             channel_selection_loc = SEQ_N_CHANNELS - 1;
         } else {
@@ -509,7 +509,7 @@ handle_channel_selection(void) {
         param_selection_loc = 0;
         redraw_trigs = true;
         redraw_params = true;
-    } else if (key_tap(KEY_DOWN)) {
+    } else if (key_retrig(KEY_DOWN)) {
         if (channel_selection_loc == SEQ_N_CHANNELS - 1) {
             channel_selection_loc = 0;
         } else {
@@ -601,7 +601,7 @@ toggle_playing(void) {
 
 void
 handle_right_col_selection(void) {
-    if (key_tap(KEY_LEFT)) {
+    if (key_retrig(KEY_LEFT)) {
         switch (right_col_selection_loc) {
             case R_COL_STOP:
             case R_COL_BANK_B:
@@ -624,7 +624,7 @@ handle_right_col_selection(void) {
         } else {
             trig_selection_loc = 7;
         }
-    } else if (key_tap(KEY_RIGHT)) {
+    } else if (key_retrig(KEY_RIGHT)) {
         switch (right_col_selection_loc) {
             case R_COL_PLAY:
             case R_COL_BANK_A:
@@ -638,7 +638,7 @@ handle_right_col_selection(void) {
             case R_COL_SETTINGS:
             case R_COL_STOP:  { input_handler = handle_pattern_selection; } break;
         }
-    } else if (key_tap(KEY_UP)) {
+    } else if (key_retrig(KEY_UP)) {
         switch (right_col_selection_loc) {
             case R_COL_BANK_A: { right_col_selection_loc = R_COL_PLAY; } break;
             case R_COL_BANK_B: { right_col_selection_loc = R_COL_STOP; } break;
@@ -650,7 +650,7 @@ handle_right_col_selection(void) {
             case R_COL_SCALE:  { right_col_selection_loc -= 2; } break;
             default: { right_col_selection_loc--; } break;
         }
-    } else if (key_tap(KEY_DOWN)) {
+    } else if (key_retrig(KEY_DOWN)) {
         switch (right_col_selection_loc) {
             case R_COL_BANK_A:
             case R_COL_BANK_B:
@@ -661,7 +661,7 @@ handle_right_col_selection(void) {
             case R_COL_STOP: { right_col_selection_loc = R_COL_BANK_B; } break;
             default: { right_col_selection_loc++; } break;
         }
-    } else if (key_tap(KEY_L)) {
+    } else if (key_retrig(KEY_L)) {
         switch (right_col_selection_loc) {
             case R_COL_BPM: {
                 s32 bpm_inc = -1;
@@ -701,7 +701,7 @@ handle_right_col_selection(void) {
                 }
             } break;
         }
-    } else if (key_tap(KEY_R)) {
+    } else if (key_retrig(KEY_R)) {
         switch (right_col_selection_loc) {
             case R_COL_BPM: {
                 s32 bpm_inc = 1;
@@ -759,7 +759,7 @@ handle_pattern_chain(void) {
     static int previous_loc = 0;
     if (key_tap(KEY_A)) {
         input_handler = handle_pattern_selection;
-    } else if (key_tap(KEY_LEFT)) {
+    } else if (key_retrig(KEY_LEFT)) {
         if (param_selection_loc == 8) {
             param_selection_loc = 15;
         } else if (param_selection_loc == 16) {
@@ -769,7 +769,7 @@ handle_pattern_chain(void) {
         } else if (param_selection_loc == 0) {
             param_selection_loc = 7;
         }
-    } else if (key_tap(KEY_RIGHT)) {
+    } else if (key_retrig(KEY_RIGHT)) {
         if (param_selection_loc < 15 && param_selection_loc != 7) {
             param_selection_loc++;
         } else if (param_selection_loc < 18 && param_selection_loc >= 16) {
@@ -885,14 +885,14 @@ handle_pattern_chain(void) {
                 }
             } break;
         }
-    } else if (key_tap(KEY_L)) {
+    } else if (key_retrig(KEY_L)) {
         if (chain.active[param_selection_loc]
                 && chain.chain[param_selection_loc] > 0
                 && param_selection_loc <= 15
                 && (!play_status || param_selection_loc != chain.current)) {
             chain.chain[param_selection_loc]--;
         }
-    } else if (key_tap(KEY_R)) {
+    } else if (key_retrig(KEY_R)) {
         if (chain.active[param_selection_loc]
                 && chain.chain[param_selection_loc] < 7
                 && param_selection_loc <= 15
@@ -934,11 +934,11 @@ handle_pattern_selection(void) {
     if (key_tap(KEY_A)) {
         input_handler = handle_pattern_chain;
     }
-    if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_RIGHT)) {
         param_selection_loc = 0;
         input_handler = handle_channel_selection;
         redraw_params = true;
-    } else if (key_tap(KEY_UP)) {
+    } else if (key_retrig(KEY_UP)) {
         if (pattern_selection_loc > 0) {
             pattern_selection_loc = pattern_selection_loc - 1;
         } else {
@@ -947,7 +947,7 @@ handle_pattern_selection(void) {
         redraw_channels = true;
         redraw_trigs = true;
         redraw_bpm = true;
-    } else if (key_tap(KEY_DOWN)) {
+    } else if (key_retrig(KEY_DOWN)) {
         if (pattern_selection_loc < 7) {
             pattern_selection_loc = pattern_selection_loc + 1;
         } else {
@@ -957,7 +957,7 @@ handle_pattern_selection(void) {
         redraw_trigs = true;
         redraw_bpm = true;
     }
-    if (key_tap(KEY_LEFT)) {
+    if (key_retrig(KEY_LEFT)) {
         redraw_params = true;
         input_handler = handle_right_col_selection;
         param_selection_loc = 0;
@@ -1032,8 +1032,8 @@ set_param_selection_sq1(ChannelSquareParams *params, InputHandler return_handler
     }
 
     // Cursor movement.
-    if (key_tap(KEY_LEFT) || key_tap(KEY_RIGHT)) {
-        if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_LEFT) || key_retrig(KEY_RIGHT)) {
+        if (key_retrig(KEY_RIGHT)) {
             if (param_selection_loc == 4) {
                 param_selection_loc = 0;
             } else if (param_selection_loc == 9) {
@@ -1073,9 +1073,9 @@ set_param_selection_sq1(ChannelSquareParams *params, InputHandler return_handler
     }
 
     // Adjust parameter.
-    if (key_tap(KEY_R) || key_tap(KEY_L)) {
+    if (key_retrig(KEY_R) || key_retrig(KEY_L)) {
         int inc;
-        if (key_tap(KEY_L)) {
+        if (key_retrig(KEY_L)) {
             inc = -1;
         } else {
             inc = 1;
@@ -1116,8 +1116,8 @@ set_param_selection_sq2(ChannelSquareParams *params, InputHandler return_handler
     }
 
     // Cursor movement.
-    if (key_tap(KEY_LEFT) || key_tap(KEY_RIGHT)) {
-        if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_LEFT) || key_retrig(KEY_RIGHT)) {
+        if (key_retrig(KEY_RIGHT)) {
             if (param_selection_loc == 4) {
                 param_selection_loc = 0;
             } else if (param_selection_loc == 7) {
@@ -1149,9 +1149,9 @@ set_param_selection_sq2(ChannelSquareParams *params, InputHandler return_handler
     }
 
     // Adjust parameter.
-    if (key_tap(KEY_R) || key_tap(KEY_L)) {
+    if (key_retrig(KEY_R) || key_retrig(KEY_L)) {
         int inc;
-        if (key_tap(KEY_L)) {
+        if (key_retrig(KEY_L)) {
             inc = -1;
         } else {
             inc = 1;
@@ -1189,8 +1189,8 @@ set_param_selection_wave(ChannelWaveParams *params, InputHandler return_handler)
     }
 
     // Cursor movement.
-    if (key_tap(KEY_LEFT) || key_tap(KEY_RIGHT)) {
-        if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_LEFT) || key_retrig(KEY_RIGHT)) {
+        if (key_retrig(KEY_RIGHT)) {
             if (param_selection_loc == 4) {
                 param_selection_loc = 0;
             } else if (param_selection_loc == 6) {
@@ -1230,9 +1230,9 @@ set_param_selection_wave(ChannelWaveParams *params, InputHandler return_handler)
     }
 
     // Adjust parameter.
-    if (key_tap(KEY_R) || key_tap(KEY_L)) {
+    if (key_retrig(KEY_R) || key_retrig(KEY_L)) {
         int inc;
-        if (key_tap(KEY_L)) {
+        if (key_retrig(KEY_L)) {
             inc = -1;
         } else {
             inc = 1;
@@ -1264,8 +1264,8 @@ set_param_selection_noise(ChannelNoiseParams *params, InputHandler return_handle
     }
 
     // Cursor movement.
-    if (key_tap(KEY_LEFT) || key_tap(KEY_RIGHT)) {
-        if (key_tap(KEY_RIGHT)) {
+    if (key_retrig(KEY_LEFT) || key_retrig(KEY_RIGHT)) {
+        if (key_retrig(KEY_RIGHT)) {
             if (param_selection_loc == 4) {
                 param_selection_loc = 0;
             } else if (param_selection_loc == 7) {
@@ -1297,9 +1297,9 @@ set_param_selection_noise(ChannelNoiseParams *params, InputHandler return_handle
     }
 
     // Adjust parameter.
-    if (key_tap(KEY_R) || key_tap(KEY_L)) {
+    if (key_retrig(KEY_R) || key_retrig(KEY_L)) {
         int inc;
-        if (key_tap(KEY_L)) {
+        if (key_retrig(KEY_L)) {
             inc = -1;
         } else {
             inc = 1;
@@ -1547,7 +1547,7 @@ handle_trigger_selection(void) {
             }
         }
         redraw_trigs = true;
-    } else if (key_tap(KEY_L)) {
+    } else if (key_retrig(KEY_L)) {
         s32 inc = -1;
         if (key_hold(KEY_SELECT)) {
             inc = -12;
@@ -1564,7 +1564,7 @@ handle_trigger_selection(void) {
             }
         }
         redraw_trigs = true;
-    } else if (key_tap(KEY_R)) {
+    } else if (key_retrig(KEY_R)) {
         s32 inc = 1;
         if (key_hold(KEY_SELECT)) {
             inc = 12;
@@ -1584,7 +1584,7 @@ handle_trigger_selection(void) {
     }
 
     // Move trigger cursor.
-    if (key_tap(KEY_LEFT)) {
+    if (key_retrig(KEY_LEFT)) {
         if (key_hold(KEY_B)) {
             if (trig_selection_loc != 0 && trig_selection_loc != 8) {
                 int next_selection_loc = MAX(trig_selection_loc - 1, 0);
@@ -1602,7 +1602,7 @@ handle_trigger_selection(void) {
             }
         }
         redraw_params = true;
-    } else if (key_tap(KEY_RIGHT)) {
+    } else if (key_retrig(KEY_RIGHT)) {
         if (key_hold(KEY_B)) {
             if (trig_selection_loc != 7 && trig_selection_loc != 15) {
                 int next_selection_loc = MIN(trig_selection_loc + 1, 15);
diff --git a/src/settings.c b/src/settings.c
index 7e86be7..9fc2f3d 100644
--- a/src/settings.c
+++ b/src/settings.c
@@ -70,7 +70,7 @@ set_audio_settings(void) {
 
 void
 handle_settings_input(void) {
-    if (key_tap(KEY_DOWN)) {
+    if (key_retrig(KEY_DOWN)) {
         if (settings_cursor_loc == (SETTINGS_NUM - 1)) {
             settings_cursor_loc = 0;
         } else {
@@ -78,7 +78,7 @@ handle_settings_input(void) {
         }
         clear_screen = true;
     }
-    if (key_tap(KEY_UP)) {
+    if (key_retrig(KEY_UP)) {
         if (settings_cursor_loc == 0) {
             settings_cursor_loc = SETTINGS_NUM - 1;
         } else {
@@ -86,7 +86,7 @@ handle_settings_input(void) {
         }
         clear_screen = true;
     }
-    if (key_tap(KEY_R)) {
+    if (key_retrig(KEY_R)) {
         switch (settings_cursor_loc) {
             case SETTINGS_SYNC: {
                 if ((settings.sync + 1) >= SYNC_NUM) {
@@ -142,7 +142,7 @@ handle_settings_input(void) {
         save_metadata();
         clear_screen = true;
     }
-    if (key_tap(KEY_L)) {
+    if (key_retrig(KEY_L)) {
         switch (settings_cursor_loc) {
             case SETTINGS_SYNC: {
                 if (settings.sync == 0) {